The latest research from the Surrey Space Centre warns that strong solar activity can dramatically increase radiation levels at typical commercial flight altitudes and create faults in aircraft electronics, potentially forcing reroutes or even grounding services on some corridors.
Radiation rises at cruising altitudes
Researchers who published their findings in the Journal of Space Weather and Space Climate examined how high-energy particles from the Sun interact with the upper atmosphere and, in turn, aviation. They found that at typical cruise heights—between 8 and 14 kilometres—cosmic radiation is substantially higher than at ground level and can surge during solar storms.
Measurements taken during a major event in November 2025 showed radiation at high altitudes climbed to almost ten times normal conditions for flights. Historical reconstructions of the strongest recorded solar storm, in 1956, suggest a single extreme event could expose air travellers to the equivalent of a year’s worth of accumulated flight-related cosmic radiation.
| Parameter | Reported figure |
|---|---|
| Typical cruise altitude | 8–14 km |
| Radiation spike (Nov 2025) | Nearly 10× normal flight levels |
| Historic 1956 event | Equivalent of ~one year of flight radiation (reconstructed) |
Electronics at risk from single-event upsets
Beyond radiation absorbed by passengers and crew, the study emphasises the vulnerability of aircraft systems to high-energy particles. These particles can induce transient errors in microelectronics known as single-event upsets (SEUs). While a single SEU might be harmless, multiple such events can accumulate and affect critical components, increasing pilot workload and posing operational hazards.
The vulnerability of avionics is not hypothetical: the industry has already seen concrete consequences. In 2025, Airbus temporarily grounded about 6,000 A320 aircraft after identifying a susceptibility in a flight-control computer to what was described as "intense solar radiation". The same year an October incident required an emergency diversion for a JetBlue flight from Cancún to Newark, illustrating how space weather can intersect with routine operations.
"intense solar radiation"
Polar routes are especially exposed
The study highlights that the weakest part of the Earth's magnetic shield lies near the poles, making trans-polar routes particularly exposed. Flights that cross the Arctic—such as services between London and Vancouver—face the greatest risk of elevated radiation and increased rates of SEUs. Researchers caution that during the most severe geomagnetic storms, these effects can extend far south of the polar regions, affecting flights over lower latitudes, including parts of the United Kingdom.
- Key operational impacts: airlines may need to reroute aircraft, delay flights or cancel services during intense events to reduce exposure and mitigate electronics risks.
- Passenger and crew exposure: cumulative radiation doses on some flights are significantly higher than at ground level and can spike during storms.
- Aircraft systems: SEUs can increase from occasional faults to hundreds or thousands per hour in extreme scenarios, complicating flight deck management.
From a weather desk perspective, space weather is a different dimension of the hazards we track. Solar flares and coronal mass ejections can rapidly alter the near-Earth particle environment in ways that affect aviation for hours to days. Airlines, air navigation providers and regulators need timely, accurate space-weather forecasting coupled with operational plans that prioritise safety.
For Canadian operations, the implications are material. Many long-haul transcontinental and intercontinental routings either cross or approach polar latitudes; when the Sun ramps up activity, those corridors can face simultaneous increases in both radiation exposure and electronics fault rates. That interplay means decisions about routing and crew exposure limits must weigh both human health and system integrity.
Advances in monitoring and forecasting, combined with improved hardening of avionics, will reduce the most acute risks. In the interim, airlines and regulators should continue incorporating space-weather warnings into operational planning so crews and passengers can be protected when the Sun turns tempestuous.
This summary is based on findings published by researchers at the Surrey Space Centre and the Journal of Space Weather and Space Climate.
